Improved dental instrument



com sata @strut @Mira news Para: No. 90,388, dans my 25,1869. 4

IMPRO'YED DEN-TAL INSTRUIEENT.

The Schedule referred to in these Letters Patent and making part 0! thenl.

To ali whom 'it ma/y concern:

Be it-known that I, W. Rf-POME'BOY, of ,Millersburg, in the county ofHolmes, and State of. .Ohio, have invented certain new and usefulImprovements in Dental Instruments; and I do hereby declare that thefollowing is a full and complete description of the same, referencebeing had to the accompanying drawings, making-a part of thisspecification, in which- Figure lA is a sideview of the instrument.

Figure 2, a view of the front edge. v

Like letters of reference refer to like parts in the several viewspresented.

This invention 4relates to a dental plugger, for condensing a filling ofmetallic foil in the cavity of a tooth, the power being applied by asuccession of blows given by a mallet, the same being operated by a ngerof the hand holding the instrument, the degree of force required beingregulated by an adjusting-screw, hereinafter more fully described.

In iig. 1, A represents a bracket, .on .the front edge of which issecured a sleeve, or socket, B, in which is inserted the shaft C of anordinary plugging-instru ment, and secured therein by a thumb-screw, D.

To the extreme rear end of said bracket is pivoted anarm, E, having ahammer or mallet, 0, attached to the free end of the same.

Also attached to the bracket is a stay, F, to serve as a support for thescrew a.

H is a coiled spring, the coiled end of which is se-I cured tothebracket, whereas the upper, or free end is attached to the arm throughthe intervention of' the link I and collar J, to which it is pivoted,thereby making an easy and flexible joint.

K is a cord, one end of which is attached to the mallet, whereas to theother is secured a thimble, L, the purpose of which will be presentlyshown. l

Having thus described the construction and arrangement of theinstrument, the practical operation of the same is as follows, viz:

The operator holds the instrument between the thum'b and first twofingers, below the sleeve referred to, or at such other point as may bethe most convenient, in order for a proper application of the point ofthe instrument to the tooth.

The position of the instrument is such that the articulation of the armE will be toward the operator,

which will bring the cord across the back of the fingers. The end of thesmall one is inserted in the thimble, whereby the hammer is operated forgiving the blows upon the upper end ofthe plugger from time to time, asthe operator may require, the force of the blows being regulated by thepower applied by the finger, also by the distance that the mallet fallsfrom its elevation, shown in fig. 1, to the end of the plugger, saiddistance being lengthened or shortened by the adjusting-screw a in theupper end of the stay F, through which it passes, and contacts with thearm E,

'against which'it'will strike on being screwed down,

thereby shortening the stroke, and lessening the force of the blow moreor less, according to the distance that the screw may be turned down.

It will be obvious, that in consequence of the pecu-` liar arrangementof the spring and link H I, the greatest resistance of the spring isobtained on the first 'start of the mallet, and, as the link approachesa hori- ,zout'al line, the leverage increases, thereby operating themallet more easily and with greater eiect than if p the resilience ofthe spring continued until the striking of the mallet. By this means, amore delicate and varied succession of blows can be given,^'therebymaking the instrument much more effective in the hands of the operatorthan the automatic pluggerand other instruments of this class now iiiuse bythe dentalpr'ofession, as in such instruments the blow is usuallygiven by a spring, which is operated by pressing the point of theinstrument upon the foil in the cavity, and, in consequence of thecontinued resistance of the spring until the blow is given, it is amatter of much diiiiculty to regulate its intensity, whereas in thislinstrument the intensity of the blow is regulated and controlled bymeans of the set-screw a, and by operating the mallet independently, bymeans of the finger. l

I am aware that a mallet has been used'in combination with a plugger.This I do not claim. But that which distinguishes my vinvention lfromothers is the special arrangementof the spring and lever-link H I,whereby the resistance of the spring is overcome by the increase of thepower of the link, or lever,'in proportion as the mallet approaches theend of the plugger, thereby giving the operator greater control over theinstrument, for regulating the force of the blow, than can be exercisedover those now in use. Also,

operating the mallet independently, by the nger, by

means of .the cord and thimble, the particularadvautage of which is,that a blow can be given with or Without pressure, or pressure without ablow, at' any time, and of any required `degree of intensity, at thewill of the operator.

Another advantage in my invention, over others, is that an ordinarydental hand-plugger is used, instead of a short point made expressly forthe instrument.'

The expense is, therefore, greatly reduced, so 'that-the dentist isenabled to use, in connection therewith, .the same kind ofplugging-instruments which are now used by hand-pressure, or with themallet and assistant.

What I claim as my invention, and desire to secure by Letters Patent, is

The adj usting-screw a, yoke F, arm E, bracket A; mallet G, and pluggerG, combined and arranged' to operate in the manner substantially asdescribed, and for the purpose specified.

Witnesses: W. R. POMEROY.

J. H. BURRIDGE, FRANKS. ALBEN.

